Following
is a portion of the RSS Definition:RSS is a family of XML file formats for Web syndication used by
(amongst other things) news websites and weblogs. The abbreviation
is used to refer to the following standards:

Rich Site Summary (RSS 0.91)

RDF Site Summary (RSS 0.9
and 1.0)

Really Simple Syndication
(RSS 2.0)

The technology of RSS allows
Internet users to subscribe to websites that have provided RSS feeds;
these are typically sites that change or add content regularly.
To use this technology, site owners create or obtain specialized
software (such as a content management system) which, in the machine-readable
XML format, presents new articles in a list, giving a line or two
of each article and a link to the full article or post. Unlike subscriptions
to many printed newspapers and magazines, most RSS subscriptions
are free. The RSS formats provide web content or summaries of web
content together with links to the full versions of the content,
and other meta-data. This information is delivered as an XML file
called RSS feed, webfeed, RSS stream, or RSS channel. In addition
to facilitating syndication, RSS allows a website's frequent readers
to track updates on the site using an aggregator.
Find the full definition at
http://en.wikipedia.org/wiki/RSS